Integrated circuit package

Abstract

A package for an integrated circuit, IC, the package comprising an interposer comprising: a first metal layer including a first metal plate; a second metal layer including a second metal plate; and a dielectric layer separating the first metal layer and the second metal layer, wherein the first metal plate and the second metal plate are arranged to form a parallel plate waveguide, PPW, and wherein the first metal plate comprises a slot for receiving one or more differential signals from the IC.

1 . A package for an integrated circuit, IC, the package comprising an interposer comprising:
 a first metal layer including a first metal plate;   a second metal layer including a second metal plate; and   a dielectric layer separating the first metal layer and the second metal layer,   wherein the first metal plate and the second metal plate are arranged to form a parallel plate waveguide, PPW, and wherein the first metal plate comprises a slot for receiving one or more differential signals from the IC.   
     
     
         2 . The package of  claim 1 , wherein the PPW is configured to combine the one or more differential signals and provide an output signal. 
     
     
         3 . The package of  claim 1 , wherein the package further comprises one or more differential feeds for receiving a respective one of the one or more differential signals, wherein each differential feed is arranged to excite the slot and the PPW in response to receiving the respective differential signal. 
     
     
         4 . The package of  claim 3 , wherein the one or more differential feeds comprise a plurality of differential feeds spaced apart along a length of the slot. 
     
     
         5 . The package of  claim 3 , wherein the one or more differential feeds form part of an IC-to-package transition connection. 
     
     
         6 . The package of  claim 3 , wherein each differential feed comprises:
 a first die-to-package signal connector arranged on the first plate on a first side of the slot; and   a second die-to-package signal connector arranged on the first plate on a second side of the slot opposite the first side.   
     
     
         7 . The package of  claim 6 , wherein the package comprises:
 a first die-to-package grounded connector arranged on the first metal plate on the first side of the slot, wherein a first die-to-package signal connector of a first differential feed is arranged between the first die-to-package grounded connector and the slot; and   a second die-to-package grounded connector arranged on the first metal plate on the second side of the slot, wherein the second die-to-package signal connector of the first differential feed is arranged between the second die-to-package grounded connector and the slot.   
     
     
         8 . The package of  claim 3 , wherein the package comprises a plurality of die-to-package grounded connectors arranged further from the slot than the one or more differential feeds. 
     
     
         9 . The package of  claim 1 , wherein the slot traverses the first metal plate with a meandering shape. 
     
     
         10 . The package of  claim 9 , wherein the PPW extends in a propagation direction from the slot to an output port of the PPW and wherein the slot comprises:
 a first portion extending in a transverse direction, perpendicular to the propagation direction, at a first position with respect to the propagation direction;   a second portion extending in the transverse direction at a second position with respect to the propagation direction, wherein the second position is offset from the first position;   a third portion extending in the propagation direction and connecting the first portion and the second portion.   
     
     
         11 . The package of  claim 1 , wherein a non-propagating end of the PPW comprises an open-ended stub or a short circuit connection. 
     
     
         12 . The package of  claim 1 , wherein the package comprises an impedance transformer extending between the PPW and an output port of the package. 
     
     
         13 . The package of  claim 12 , wherein the impedance transformer is realised in the first metal layer or the second metal layer and the impedance transformer comprises:
 a first quarter-wavelength impedance transformer in the respective first or second metal layer comprising a metal strip having a width less than a width of the respective first or second metal plate.   
     
     
         14 . The package of  claim 1 , wherein the package comprises an output port, wherein the output port comprises a single-ended output in the first or second metal layer and an integrated coaxial connection. 
     
     
         15 . A packaged IC comprising:
 an IC;   a first metal layer including a first metal plate;   a second metal layer including a second metal plate; and   a dielectric layer separating the first metal layer and the second metal layer, wherein the first metal plate and the second metal plate are arranged to form a parallel plate waveguide, PPW, and wherein the first metal plate comprises a slot for receiving one or more differential signals from the IC.   
     
     
         16 . The package of  claim 2 , wherein the output signal comprises a single-ended output signal and the package comprises an output port for coupling the single-ended output signal to a printed circuit board, PCB. 
     
     
         17 . The package of  claim 10 , further comprising:
 a first differential feed for receiving a first differential signal of the one or more differential signals, wherein the first differential feed is arranged on either side of the first portion of the slot; and   a second differential feed for receiving a second differential signal of the one or more differential signals, wherein the second differential feed is arranged on either side of the second portion of the slot.   
     
     
         18 . The package of  claim 13 , wherein the impedance transformer comprises a second quarter-wavelength impedance transformer in the respective first or second metal layer comprising a metal strip having a width less than the width of the first quarter-wavelength impedance transformer. 
     
     
         19 . The package of  claim 14 , wherein the single-ended output comprises a microstrip or a grounded co-planar waveguide. 
     
     
         20 . The package of  claim 14 , wherein the integrated coaxial connection comprises:
 a central via extending from the microstrip to a third metal layer for connection to a package-to-printed circuit board, PCB, interface; and   a circular array of vias extending from the first metal layer to the third metal layer.